The invention relates to a method for conserving (or: preserving) biological material in the deep sea, in particular to a method for capturing or collecting at least one biological organism in the deep sea and transferring it to surroundings under normal pressure. Moreover the invention relates to a conservation apparatus which is designed for conserving biological material in the deep sea. Applications of the invention are the retrieval and culturing of biological material from the deep sea.
Various methods are known for characterizing biological material. While genomic analysis may be carried out on dead biological material, biochemical analyses at a molecular, cellular or physiological level require the presence of viable cells in the living organism or in an in vitro culture. An in vitro culture in particular makes it easier to carry out laboratory methods and to use instruments for characterizing the biological material and to make biotechnological or pharmacological use of the biological material. While standard methods are known for the in vitro culturing of cells from most organisms living on the earth's surface at normal pressure, considerable limitations apply to the investigation of biological material whose natural habitat is the deep sea (depth below 2000 m, for example below 2300 m or 4000 m, abyssal, in particular below 5000 m to 11000 m, hadal).
Biological cells from deep-sea macrofauna organisms have hitherto only been successfully isolated and cultured down to a depth of around 1200 m (see S. Koyama in “Kryotechnology”, volume 55, 2007, pp. 125-133). These methods are, however, restricted to organisms which can tolerate a pressure drop in the hydrostatic pressure of their habitat down to normal pressure (atmospheric pressure), i.e. which are not obligate barophiles, such as for example the deep-sea eel. The methods described by S. Koyama are, however, not applicable to the majority of deep-sea organisms, because they live at considerably greater depth, in particular below 3000 m and are typically not barophilic. Biological organisms from the deep sea are therefore not yet represented in laboratory cell cultures, or accessible for investigations at the earth's surface. Attempts have also been made to retrieve living organisms from great depths and to keep them alive in the laboratory and at the surface in pressurized aquariums or by adaptation to normal pressure. Such attempts have, however, only met with success down to a depth of 2300 m (see B. Shillito et al. In “Deep-Sea Research I” volume 55, 2008, pp. 881-889).
In practice, the reasons behind the so far unsuccessful attempts to retrieve living cell material and to establish viable in vitro cell cultures which are stable over the long term are considered to be that, with increasing depth, organisms become increasingly adapted to high pressures and to high pressure constancy in their natural habitat, and in the deep sea an adaptation to a constantly low or, near hot springs, high temperature and a low tolerance to temperature changes have developed, and that, at great depths, in particular deeper than 5000 m, the organisms are generally barophilic. It may furthermore be assumed that the macromolecules involved in cellular biological processes are optimized for high pressures (up to 110 MPa at a depth of 11,000 m) and reduce or completely lose their function at lower pressures.
Capture gear for collecting biological organisms in the deep sea and transferring them to the surface while maintaining cell vitality is not yet available. Furthermore, the technical limitations involved in handling living organisms, such as in animal keeping, cell culturing or isolation methods, under high pressures have not yet been overcome. Another problem which arises here is the considerable time pressure which occurs when transporting organisms from the deep sea to the earth's surface. Because of these limitations, only little information is so far available about which biological cells may be cultured, isolated and/or multiplied from what kinds of tissue.
The objective of the invention is to provide an improved method for conserving biological material from the deep sea, with which the disadvantages and limitations of conventional techniques may be overcome and which in particular makes it possible to retrieve at least one biological organism from the deep sea while maintaining the viability of its cells and to transfer the cells into a stable in vitro culture capable of multiplication. It is furthermore an objective of the invention to provide an improved conservation apparatus, with which the disadvantages and limitations of conventional techniques may be overcome and which has an extended range of applications in collecting biological organisms in the deep sea.
These objectives are achieved by a conservation method and a conservation apparatus of the invention.